Which term is described as disc-like structures used to attach to surfaces?

Which term is described as disc-like structures used to attach to surfaces?

• A. Bristles
• B. Cilia
• C. Worm cast
• D. Suckers

Answer: (D)

Disc-like attachment structures are suckers. They form a circular or oval disc that can seal against a surface, and muscles or pressure differences inside the disc create suction to hold the organism in place. This is why you see them on leeches, which use anterior and posterior suckers to cling to hosts, and on many octopus tentacles, where suction cups grab and secure objects or surfaces. Bristles are hair-like projections used for grip or movement, not suction cups. Cilia are tiny beating hairs that move fluids or help with locomotion, not attachments. A worm cast is simply worm excrement, not a structure for attaching.